Step bearing for gyratory crusher



April 14, 1970 R. H. KEMNITZ L STEP BEARING FOR GYRATORY CRUSHER 2Sheets-Sheet 1 Filed Oct. 12, 1967 A 5 J A w Wm /M M: w mmwf April 14,1970 v H KEMNlTz ET AL 3,506,204

STEP BEARING FOR GYRATORY CRUSHER Filed Oct. 12. 1967 2 Sheets-Sheet 2A8 Q MMk /Qp @ww 314mm):

United States Patent US. (1. 241208 4 Claims ABSTRACT OF THE DISCLOSUREA step bearing for a gyratory crusher head comprising a pad member ofelastomeric material, preferably rubber, which is interposed beneath thesurface of a gyratory crusher head or of a part in supporting relationthereto in such manner that the elastomeic or rubber pad absorbs shockloads or the like substantially instantaneously.

BACKGROUND OF THE INVENTION Field of the invention This inventionrelates to gyratory crushers and more particularly to an improved stepbearing for such a crusher.

Description of the prior art It is well known in the art of gyratorycrushers that it is necessary to support the gyrating crusher head bymeans of a step bearing. For example, in United States Patent No.2,448,936, issued to C. C. Van Zandt on Sept. 7, 1948, there is shown astep bearing for supporting the lower end of the main shaft 2 on whichthe crusher head is mounted. Another example of a step bearingconstruction is shown in United States patent application Ser. No.537,868, which shows a spiderless type crusher in which the verticallyadjustable crusher head is supported on a step bearing at the upper endof the slidably adjustable vertical post beneath the crusher head. It isalso known to support a spiderless type crusher head by a step bearinglocated beneath the outer periphery of the crusher head.

All of the step bearing constructions of the prior art, such as thoseexemplified by the prior art just mentioned, are formed of rigidmaterials which are not capable of yielding under sudden impact loadswhich might be caused, for example, by the presence of large pieces ofnoncrushable material, or tramp iron in the crushing chamber. While itis known in the prior art to provide hydraulic relief arrangements whichpermit a downward movement of the crusher head when tramp iron ispresent, the response time required for such downward movement isfrequently greater than might be desirable.

SUMMARY OF THE INVENTION Accordingly, it is an object of this inventionto provide a step bearing construction for a gyratory crusher in whichthe bearing provides an initial relief for shock loads such as thosecaused by tramp iron passing through the crushing chamber.

It is another object of the invention to provide a step bearingconstruction for the gyrating crusher head of a gyratory crusher whichis less expensive than step bearing constructions of the prior art.

It is still a further object of the invention to provide step bearingconstruction (for a gyratory crusher the use of which results in lesstendency for the crusher to pack than in constructions of the prior art.

In achievement of these objectives, there is provided in accordance witha preferred embodiment of the present invention a step bearing for agyratory crusher head comprising a pad member of elastomeric material,preferably rubber, which is interposed beneath a surface of the gyratorycrusher head or of a part in supporting relation thereto in such mannerthat the elastomeric or rubber pad absorbs shock loads or the likesubstantially instantaneously.

Further objects and advantages of the invention will become apparentfrom the following description taken in conjunction with theaccompanying drawings in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in vertical sectionof a gyratory crusher embodying the improved step bearing constructionof the invention;

FIG. 2 is a view in vertical section of a modified step bearing havingonly an elastomeric bearing element;

FIG. 3 is a view in vertical section of a still further modified stepbearing arrangement having an elastomeric bearing element of conicalupper contour;

FIG. 4 is a schematic diagram of the compressive effect of the crusherhead on an elastomeric pad of fiat upper surface;

FIG. 5 is a schematic diagram of the compressive effect of the crusherhead on an elastomeric pad of conically tapered upper surface; and

FIG. 6 is a view in vertical section showing the engagement of thecrusher head with a bearing pad of spherical upper contour.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawingsand more particularly to FIG. 1, there is shown a gyratory crushergenerally indicated at 10 including a base frame housing 12 having adrive housing portion 14 and a pedestal-like cylindrical hub portion 16extending vertically upwardly at right angles with respect to drivehousing 14. A sleeve shaped lower outer frame structure 18 having aflange 20 is concentrically disposed around the cylindrical hub 16 andis secured to the base frame housing 12 by a plurality of radial supportstruts 22. An upwardly open upper frame structure 24 having a flange 26is secured horizontally to the lower outer :frame 18 at flange 20 by anymeans such as by a plurality of bolts 28. A removable bowl liner orconcave ring 30 is secured horizontally within upper frame 24concentrically above hub 16 by any means such as by plurality of bolts32.

A cylindrical crusher post 34 having a flange or head portion 36 at theupper end thereof, is concentrically and slidably fitted Within thecylindrical hub 16 of the base frame structure 12 and projectsvertically upwardly into the space defined by the bowl liner or concave30. The lower end of the crusher post 34 is secured to a piston 38 Whichis slidably fitted within cylinder 40 in the lower portion of the baseframe housing 12. Hydraulic fluid or the like may be admitted to thecylinder 40 through the passage 42 to permit vertical upward adjustmentof crusher post 34 as may 'be required. Circular bearings and seals 44are provided at the upper and lower extremities of the bore throughcylindrical hub 16 to slidably support the crusher post 34 within thehub 16, and to form an annular fluid chamber 46 between hub 16 and thecrusher post 34. A fluid passage means such as a tube 48' is provided tocommunicate between the annular chamber 46 and the upper surface of thehead portion 36 of the crusher post 34. A suitable fluid passage meansextends from the annular fluid chamber 46 to a point outside the baseframe housing 12 to permit introduction of a fluid lubricant into theannular chamber 46.

In accordance with the invention, a shock absorbing and self-aligningstep bearing generally indicated at 52 is provided and includes a metalbearing plate 54 formed of a suitable metal such as bronze and anelastomeric pad 56 of rubber or other elastomeric material which issuitably secured, as by vulcanizing, to the upper surface 3f the metalplate 54. In the illustrated embodiment of FIG. 1, the rubber pad 56 isof cylindrical cross section and has a flat upper surface. The undersurface of the Jronze bearing plate 54 extends in a horizontal planeaarallel to the upper surface of head portion 36 of a crusher post 34. Aconical crusher head 58 is adapted to seat on the upper surface of thestep bearing 52, the flat under surface of the upper end of the crusherhead being recessed slightly as indicated at 60 to receive and locatethe upper edge of the rubber pad 56. The upper end of the crusher headis provided with an integral threaded extension indicated at 62. Aconical crusher wearing mantle 64 is symmetrically positioned over theconical surface of crusher head 58 and is held in place by a suitablemeans such as a nut 66.

An annular eccentric sleeve 68, having a ring gear 70 secured to thelower end thereof, is rotatably mounted on the cylindrical hub portion16 of the base frame housing 12 and rests against a circular thrustbearing 72 se- :ured to base frame 12. Bearing sleeve 74 is disposedbetween hub portion 16 and eccentric sleeve 68 to facilitate rotation ofthe eccentric sleeve 68 on the hub portion [6. The outer circumferenceof the eccentric sleeve 68 mates with the inner circumference of theskirt 76 on the crusher head, and a bearing sleeve 77 is carried by thecrusher head skirt 76 to facilitate rotation of the eccentric sleeve 68within the skirt 76. The outer cylindrical surface of the eccentricsleeve 68 is inclined relative to the vertical axis A of the cylindricalhub 16 about which the eccentric sleeve rotates, to provide a tilting ofthe axis A of the crusher head by an angle 0.

A drive shaft 78 extends through the drive housing 14 on base frame 12and a pinion gear 80 is secured to shaft 78 and in meshing engagementwith the ring gear 70. Rotation of shaft 78 by an external power source(not shown) rotates pinion gear 80 to rotate ring gear 70 and thus torotate the eccentric sleeve 68 about the hub Rotation of eccentricsleeve 68 imparts gyratory motion to crusher head 58. Due to the angularinclination of the axis A of the crusher head relative to the axis A ofthe crusher post, the rubber pad 56 is more highly compressed to theleft-hand of the axis A with respect to the view shown in FIG. 2 at thegiven moment then it is to the right of the axis A and further there isa bulging of the material of the rubber pad away from the region ofgreatest compression or to the right with respect to the view shown inFIG. 2. The location of the compressed and bulged regions of the rubberpad changes from moment to moment with the gyratory motion of thecrusher head. During the gyratory motion of the crusher head, the metalnearing plate 54 slides along the upper surface of post 36. Fluidlubricant passes from the upper end of tube 48 to radial slots 55 inhead portion 36 of the crusher post to provide lubrication for thesliding motion of metal plate 54.

Referring now to FIG. 2, there is diagrammatically shown therein amodified step bearing which is generally similar to the step bearing ofFIG. 1, except that it :liminates the bearing plate 54 of FIG. 1 andcomprises elastromeric or rubber pad 86 which is mounted directly onhead portion 90 of crusher post 88. The upper surface or the headportion 90 is provided with a periph- :ral retaining lip or the like 92which serves to retain :he rubber bearing pad 86 in position withrespect to :he head portion 90 of the crusher post. The crusher head isgenerally indicated at 94. The crusher post lies on a vertical axis Awhich is perpendicular to the horizontal plane, whereas the crusher head94, as it gyrates, lies along an axis A which is inclined away from thevertical axis A of the crusher post by an angle 6.

The elastomeric bearing pad 86 in the view of FIG. 2 s of substantiallycylindrical cross section in its undistorted shape and includessubstantially flat upper and lower surfaces. As the crusher head gyratesduring its operation, the frictional engagement between the undersurface of the crusher head, which is in bearing engagement with theupper surface of the elastomeric bearing pad 86, tends to drag the uppersurface of the pad 86 with it during the gyratory motion of the crusherhead whereas the lower surface of the bearing pad 86 is retained by theretaining lip 92. Thus, the gyratory motion of the crusher head willtend to impart a distortion to the bearing pad 86 in accordance with thegyrations of the crusher head, the portion of the bearing pad which isdistorted varying from moment to moment with the gyrations of thecrusher head.

Referring now to FIG. 3, there is shown a still further modified form ofstep bearing arrangement which is generally similar to that of FIG. 2 inthat it provides a step bearing formed of an elastomeric or rubber padgenerally indicated at 96 which rests on the head portion 100 of crusherpost 98. Head portion 100 is provided with a retaining lip 101 whichprevents shifting of the lower portion of pad 96. As in the embodimentof FIG. 2, the axis of the crusher head 102 is inclined at an angle 0with respect to the vertical axis of the crusher post 98 which lies in avertical plane perpendicular to the horizontal plane. The fiat undersurfare 104 of crusher head 102, which lies perpendicular to thevertical axis of the crusher head, is therefore inclined at an angle 6with respect to the horizontal plane. The elastomeric bearing pad 96 isprovided with a generally cylindrical base or lower portion 106 whichextends upwardly for a portion of the height of pad 96. However, theupper end portion of pad 96 is provided in the embodiment of FIG. 3 witha conically tapered surface 108 having a conical angle 5 which is equalto or close to the angle of inclination 9 of the under surface 104 ofthe crusher head due to the tilt of the crusher head, so that under noload conditions on the crusher head, the flat under surface 104 of thecrusher head will substantially engage the entire radial width ofelastomeric pad 96, making at least a line contact at no load and anarea contact under load, due to the equality of the tilt angle of thecrusher head and of the cone angle of the upper end surface of pad 96.The use of the conically tapered bearing pad 96 as shown in FIG. 3 hasan advantage over the flat upper surface bearing pad 56 as shown in FIG.1 in that the conical bearing pad 96 reduces the maximum unit load onthe bearing pad as compared to the fiat top surface bearing pad as canbest be seen by the graphical analysis of FIGS. 4 and 5.

As seen in FIG. 4, 86 represents the rubber bearing pad shown in FIG. 2while 94 represents the crusher head the under surface of which isinclined by the angle 0 with respect to the horizontal plane due to theoperating tilt of the crusher head. The bearing pad 86 has a flat uppersurface; hence when the crusher head is under no load conditions, itwill eifect a compression of the upper surface of the bearing pad by anamount equal to Y engaging substantially only the outer edge region ofbearing pad 86. At the ordinary crushing load, the bearing pad willdepress an additional amount indicated by Y whereas at overload thebearing pad will be depressed a still additional amount indicated by YIn contrast, when using the bearing pad 86 of FIG. 3 having the taperedupper surface 108, under no load conditions the crusher head 102 willassume a position such that the under surface of the crusher head issubstantially parallel to a radial line on the conical upper surface ofthe bearing pad 96 and effects only a very slight depression of theelastomeric material of the pad, which can be ignored for practicalpurposes. At ordinary crushing loads, crushing head 102 depresses thematerial of the pad 96 to a level substantially that of a line indicatedat C. L, while at overloads the material of the pad is depressed to theoverload line indicated by O. L. It can be seen from a comparison ofFIGS. 4 and 5 that under ordinary crushing load conditions, thecompression exerted on the flat-topped pad 86 of FIGS. 2 and 4 isrepresented by the sum of the compressions Y +Y whereas under crushingload conditions on the conically tapered crusher pad of FIGS. 3 and 5,the compression on the pad is represented only by Y Similarly, atoverload conditions on the crusher, in the flat-topped embodiment ofFIGS. 2 and 4, the overload compression on the pad is represented by thesums Y +Y +Y while at overload conditions on the crusher on theconically tapered bearing pad of FIGS. 3 and 5, the compression isrepresented merely by the sum of Y +Y It can be seen, therefore, thatthe maximum unit load on the crusher pad is greater with the flat-topbearingpad 86 of FIGS. 2 and 4 under any given condition of operationthan in the case of the bearing pad 96 having the conical upper surfaceof FIGS. 3 and 5.

There is shown in FIG. 6 a further modified embodiment in which a stepbearing 110 formed of an elastomeric material such as rubber is seatedon the upper surface of head portion 114 of crusher post 112. Thebearing pad 110 is provided with a flat bottom surface which rests onhead portion 114. Pad 110 is of cylindrical cross section for theportion of the height thereof indicated at 116. The upper end surface ofthe pad 110 in the embodiment of FIG. 6 is of spherical contour asindicated at 118. The embodiments shown in FIGS. 3 and 6 in which theupper surface of the bearing pad are respectively of conical and ofspherical contour are the preferred embodiments of the rubber orelastomeric bearing pad.

In either of the forms of the step bearing shown in FIGS, 3 and 6, therubber bearing pad 96 or 110 may be secured as by vulcanizing to theupper surface of a metal bearing plate such as the plate 54 of theembodiment of FIG. 1.

It can be seen from the foregoing that there are provided in accordancewith this invention step bearing constructions for gyratory crusherswhich have advantages over prior art step bearing arrangements. The useof the elastomeric or rubber bearing pads permits the crusher head torespond quickly to shock loads such as those which might be caused, forexample, by the presence of large pieces of noncrushable material ortramp iron in the crushing chamber. The elastomeric step bearing absorbsthe initial high intensive shock loads caused by the passage of thetramp iron or the like while the final relief is provided by thehydraulic relief system of the crusher, if such is provided.

Furthermore, the various step bearing constructions hereinbeforedescribed are less expensive than the all metal step bearingconstructions of the prior art.

While there have been shown and described particular embodiments of theinvention, it will 'be obvious to those skilled in the art that variouschanges and modifications may be made therein without departing from theinvention and, therefore, it is aimed to cover all such changes andmodifications as fall within the true spirit and scope of the invention.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. In combination, a gryatory crusher comprising a crushing bowl, acrushing head mounted for gyratory movement relative to said bowl,support means supporting said crushing head for gyratory movement, anelastomeric bearing member superposed above a metal bearing member, bothsaid bearing members being interposed between said support means andsaid crushing head.

2. In combination, a gyratory crusher comprising a crushing bowl, acrushing head mounted for gyratory movement relative to said bowl,support means supporting said crushing head for gyratory movement, andan elastomeric 'bealring member interposed between said support meansand said crushing head, the upper surface of said elastomeric bearingmember being of conical shape.

3. In combination, a gyratory crusher comprising a crushing bowl, acrushing head mounted for gyratory movement relative to said bowl,support means supporting said crushing head for gyratory movement, andan elastomeric bearing member interposed between said support means andsaid crushing head, the upper surface of said elastomeric bearing memberbeing of spherical shape.

4. In combination, a gyratory crusher comprising a crushing bowl, acrushing head mounted for gyratory movement relative to said bowl,support means supporting said crushing head for gyratory movement, anelastomeric bearing member interposed between said support means andsaid crushing head, the upper surface of said elastomeric bearing memberbeing of conical shape, the axis of said crusher head being inclined atan angle with respect to the vertical, the under surface of said crusherhead which bears on said bearing member being substantially fiat andlying in a plane substantially perpendicular to the axis of said crusherhead, said elastomeric bearing member having a conical angle such thatsaid under surface of said crusher head lies in a plane substantiallyparallel to a radial line on the conical surface of said elastomericbearing member.

References Cited UNITED STATES PATENTS 653,679 7/ 1900 Kimble 241211787,737 4/1905 Durnholz 241211 2,556,641 6/1951 Bakewell 241-286 FOREIGNPATENTS 71,375 7/1950 Denmark.

7 GERALD A. DOST, Primary Examiner US. Cl. X.R.

